Tucking and drop-stitch mechanism for knitting machines



4 F. w. ROBINSON.

TUCKING AND DROP STITCH MECHANISM FOR KNITTING MACHINES.

APPLICATION FILED MAYZI, I9I9. 1,402,379.

Patented Jan. 3, 1922,

FRANK W. ROBINSGN, (3F READING, EENNSYLVANIA, ASSIGNOR TO THE NULDE 5tHORST (30., OF READING, PENNSYLVANIA, A CORPORATION 03? PENNSYLVB""TUCKING AND DROP-STITCH MECHANESIII FOR KNITTING MACEINES.

mea re.

Application filed may 21,

T 0 all whom it may con cern Be it known that I, Fmnn W. ldonrnson, acitizen of the United States, residing at the city of Reading, in thecounty of Berks and State of Pennsylvania, have invented certain new anduseful Improvements in Tricking and Drop-Stitch ll lechanism forKnitting Machines, of which the following is a specification.

My invention relates to circular knitting machines, and it consists inimproved mechanism providing for continuous knitting with desiredvertical stripinqs spaced around the whole circumference, as of the legportion of a stocking, or upon a part only of such circumference as isdesired in a stocking foot. The invention is fully described inconnection with the accompanying drawing and particularly pointed out inthe claims.

Fig. 1 is a diagrammatic view of a knitting cam mechanism embodying mypresent invention,

Fig. 2 illustrates a circular series of needles having different lengthsof butts operative by said cam mechanism as hereinafter described;certain thereof with relatively long latches beingindicated by heavierlines.

Fig. 3 is a detail plan view of the butt engaging end portion of thesupplemental longlatch clearing cam employed.

Fig. 4 indicates a stocking product of my improved mechanism; and Fig. 5the lacestripe eil'ect particularly provided for.

Fig. 6 further indicates the differences in needle latches and buttsdiagrammatically illustrated in Fig. 2.

The circular series of needles indicated in Fig. 2 is divided intoapproximately halfcircle series, of long-butt needles 0, and shortbutt.needles 7) respectively, for circular or reciprocative knitting as usualin the production of stockings. Certain of these needles, as a a of thelong butts and 7) Z) of the shortbutts, difier from the others in beingprovided with relatively long latches adapted to hold their loops unlessspecial clearing movement is imparted to them; and drop stitch etlectsare provided for, as indicated, by the omission of determined needles ofthe long butt series as at 0, a and by providing determined needles b ofthe short butt series with butts of intermediate length adapting them tobe thrown into or out of knitting action as desired.

Specification of immense. Patented e, 1922 1919. Serial Tilt. 298,577.

By, proper operation of needles formed and arranged in such manner as isindicated, tucking effects may be produced, in connection with dropstitch effects as desired; and the particular purpose of my presentinvention is to provide for so operating the needles as to enable thcontinuous production of such tucking efl'ects, preferably in connectionwith drop stitches so as to produce lace stripes as indicated in Figs. 4and 5, upon the entire leg portion of a stocking as is generallydesired, and upon the upper portion only of the tubularly knitted foot.

The general arrangement and operation of cam mechanism for directlyactuating the needles being well known, my present improvements may beclearly explained in connection with the diagrammaticshowing of Fig. 1,where the usual center cam is indicated at 2, and the usual left handlatch clearing cam at 3. In connection with the corresponding right handlatch clearing earn 4 is provided a long-latch clearing cam 5 adapted tobe thrown into or out of cooperative relation therewith as particularlyset forth in my pending application Ser. No. 292,262 filed Apr. 2&,1919, so as to either raise all the needles sufiiciently to clear theirloops as required for ordinary knitting, or'to cause determined loops togather upon the long latch needles as desired for tucking.

Below the normal needle run-way 10 is provided a lower run-way 11connected by reversely inclined branches 12, 13, which branches areguarded respectively by amovable dividing cam 1415 in connection with afixed relowe-ring cam 16, and by a return switch cam 17, as shown in myPatent No. 1,339,715, dated May 11, 1920. In my presentimprovedconstruction I provide additional cams 20, 21, 22, which may be combinedin asingle device as indicated so as to be jointly movable. into and outof the needle path; the face of .cam being set back so as to loweringlyengage the longer butt needles only; while cam 21 is arranged to' raisethe shorter butt needles sufficiently to clear loops from the longlatched ones also (for ordinary knitting as in the lower foot portion),and cam 22 to relower the same; different courses taken by therespective needles as controlled by the comple e cam mechanismshoWn,-being indicated in Fig. 1 by distinguishing lines referred to inthe following description.

10 W t"? VET ch ins sing 7 5 comp ri the m 1 pil the Yet the 11m"nzmrned lwring mitting 50 knittim

